These studies are designed to increase our understanding of the epidemiology, significance, pathogenesis, and control of mosocomial urinary tract infections in hospitalized patients who receive indwelling urethral catheters. In the past four years, we have established a program for the daily bacteriologic monitoring of urinary drainage systems and, using a unique computerized medical records system, developed techniques for implementing prospective, randomized, controlled studies of preventive methods. In recent studies, we have identified bacterial colonization of the urethral meatuscatheter junction as an important risk factor for later bacteriuria, and demonstrated the failure of prevention using an iodophor disinfectant applied twice daily to the meatal surface. We will continue these studies by evaluating other topical antimicrobials for meatal care as well as other preventive approaches, such as the use of silicone catheters, weekly changes of catheters, and systemic treatment with trimethoprim-sulfamethoxazole. We will continue our long-term epidemiologic studies of the incidence and associated risk factors for catheter-related gram-negative bacteremia. We propose to evaluate a test for antibody-coating of urinary bacteria as an epidemiologic tool to predict morbidity and persistance of bacteriuria. We will utilize our monitoring system to develop techniques to eliminate unnecessary catheterization and to encourage early removal of catheters. The ultimate goal of our project is to develp practical methods for prevention and control of catheter-assocated infections that can be used in all hospitals. Toward this end, we will implement and test suitable methods in a nearby private hospital that has not been the site of previous study.